Mining machine



May 4, 1937'.

M, P. HOLMES MINING MACHINE Filed Febj 27, 1933 v v3 Sheets-Sheet 1` May 4; 1937. M. P. HQLMES 2,078,944

MINING MACHINE Patented May 4, 1937 PATENT OFFICE i 2,078,944 MINING MACHINE Morris P. Holmes, Claremont, N. H., assignor to Sullivan `Machinery Company, a corporation of Massachusetts Application February 27, 1933, Serial No. 658,803

24 Claims.

This invention relates to mining machines, and more particularly to improvements in the feeding mechanism of a mining machine of the flexibly fed, continuous cutter type.

An object of this invention is to provide an improved mini-ng machine. Another object is to provide an improved mining' machine feeding mechanism. A further object is to provide an improved mining machine of the flexibly fed, continuous cutter type having improved flexible `feeding means. Yet another object is to provide, in a machine of the above character, an improved flexible feeding mechanism wherein. relatively rotatable feed operating and controlling members cooperating with exible feeding elements are employed, the feed operating and controlling members having improved driving and controlling means whereby the machine may be fed and`cntrolled in an improvedvmanner'. Still another object is to provide, in a room-and pillar mining machine, an improved variable speed driving means whereby the feed operating and controlling members may be driven through a Wide range of relativelylow feeding speeds between zero and a predetermined maximum, the feeding mechanism also having embodied therein improved high speed driving means for effecting drive of the feed operating and controlling members at a relatively high predetermined machine moving speed. These and other objects and advantages of `theI invention will, however, hereinafter more fully appear. i

In the accompanying drawings there is shown for purposes of illustration one form which the invention may assume in practice.

In these drawings,-

Fig. l is a plan view of a coal mining machine having embodied therein the illustrative form ofv the improved feeding mechanism, Y

Fig. 2 is a side elevational view of the machine shown in Fig. 1.

Fig. 3 is a longitudinally extending vertical f tially on line 'l--l of Fig. 4,

(CIL 262-30)`V n Fig. 8 is a detail sectional view taken on line 8--8 of Fig. 6.

In this illustrative form of the invention the improved feeding mechanism is shown embodied in a coal mining machine of the exibly fed,

continuous cutter, room and pillar type, although it is evident that the improved feeding mechanism may be embodied in coal mining machines of various other types. Themining machine disclosed herein generally comprises a machine 10 frame l having a plane bottom surface 2 on which` the machine is slidably supported for sliding movement over the mine oor. Rigidly secured within the lower portion of the machine frame,

and projecting forwardly therefrom is an elon 15` gated plane cutter bar 3 having mounted on its margin for circulation thereabout an endless cut-` ter bit carrying cutter chain 4, the bottom portionV of the machine frame having extending 1ongitudinally therethrough a cutter chain passage 5 Within which the cutter vchain operates, in the mannerA usual in mining machines of the room and pillar type. Mounted on the machine frame and superimposed above the cutter bar 3 at the forward end of the machine frame is a motor casing 6 housing a horizontal motor of aV low, compact design, herein preferably of the' reversible electric type, having its armature shaft l horizontally` disposed and extending longitudinally of the machine. Arranged at the ing and controlling elements Il and l2. The rear 40- end of the motor shaft is operatively connected to the cutter chain driving means and the improved driving mechanism for the feed operating and controlling members in the manner toV be hereinafter described. As is usual in machines of the room and pillar type, there are arranged at the opposite front corners of the machine frame suitable guide sheaves Ill and l5, herein mounted on swing arms I6, pivotally mounted at il within lateral recesses I8 formed in the opposite sides of 50` the machine frame for vertical swinging movement, while arranged on the opposite sides of the machine on axes parallel with the axes of the feed operating and controlling members and in advance of the latter are guide sheaves i9 and 55 22. Also arranged in transverse planes beneath the feed operating and controlling members at the rear end of the machine are guide sheaves 2|, 22, 23 and 24, herein disposed on vertical axes and in sets, two at each rear corner of the machine. The feed operating and con trolling elements I i and I2 may be extended from the feed operating and controlling members around the guide sheaves I4, i5, i9, 2G, 2|, 22, 23 and 24 in various manners and in any preferred direction, as is well known to those skilled in` the art. As is usual in room and pillar machines, during cutting from right to left, the feed operating element II is extended from the feed operating member 9 forwardly along the advancing side of the machine -around the front guide sheave I4 and then laterally along the coal face to a suitable anchor disposed at the left hand rib, While the controlling element I 2 is extended from the controlling member I0 around the guide sheave 24 laterally from the rear corner of the machine at the receding side of the machine to a suitable anchor located adjacent the right hand rib. The feed operating and controlling members are then operated to wind in their respective ilexible feeding elements to effect sumping of the cutter bar beneath the coal and lateral feeding of the machine transversely across the coal face. During cutting from left to right the feeding and controlling elements are extended fro-m the machine in an opposite manner. Y

Now referring to the driving means for the cutter chain, and more particularly to the improved driving means for the feeding mechanism, it will be noted that xed to the rear end of the motor power shaft 'I is a spur pinion 25 meshingV with a spur gear 2S arranged on an axis parallel with and below the motor shaft axis and journaled on a stub shaft 27 suit-ably fixed within the machine frame. Secured to and rotatable with the spur gear 276 is a bevel pinion 28 meshing with a large bevel gear 2S disposed in horizontal planes directly above the cutter chain passage 5 for rotation about a vertical axis. This bevel gear has its hub portion 3Q keyed at 3| to a vertical main feed driving shaft 32, herein journaled at its opposite ends within suitable bearings 33 carried within the top and bottom portions of the feed frame in the manner shown in Fig. 3. Supported on the hub of this bevel gear is a bearing sleeve 34 on which there is rotatably mounted a chain sprocket 35 which engages and drives, in the usual manner, the cutter chain 4. The hub of the cutter chain sprocket and the sleeve and shaft structure project through a circular opening 36 iny a transverse partition 31 of the feed frame, and carried by this partition and encircling the hub of the sprocket is a packing ring 38 for preventing access of dirt to the internal mechanism and for preventing leakage of oil from the interior of the feed frame. A similar ring 39 is interposed between the bearing sleeve 34 and a step plate 4@ attached to the bottom of the feed frame. In the present construction, slidably mounted on the shaft 32 is a clutch element 4I having teeth projecting within slots 42 in the bevel gear and engageable with sockets 43 formed in the upper end of the sprocket hub; the clutch member 4I being slidable downwardly to interlock the bevel gear with the sprocket, thereby to effect drive of the cutter chain. Connected to this clutch member 4I and slidably mounted on the shaft 32 is a clutch operating sleeve 44 .having upstanding ears 45 pivotally connected at 46 to shipper arms 41 fixed to a transverse operating shaft 48. This operating shaft is arranged transversely of the machine frame and has fixed thereto at the advancing side of the machine an operating lever 49.

Now referring to the feed driving mechanism per se, it will be noted that formed integral with the shaft 32 above the bevel gear 29 is a worm 50, herein` a high speed worm, meshing with a high speed worm wheel 5|, herein journaled on a horizontal shaft 52 herein arranged transversely of the machine frame and suitably journaled within suitable bearings at the sides of the feed frame. Herein mounted on and coaxial with the shaft 32 and surrounding the upper end thereof is a spur pinion 53 meshing, as shown in Fig, 5, with a spur gear 54, keyed to a vertical shaft 55 herein arranged parallel with the shaft 32 at one side thereof and likewise suitably journaled within the feed frame. Herein formed integral with the shaft 54 in parallel relation with the worm 50 is a Worm 56, herein a low speed worm, meshing with a low speed worm wheel 5l likewise journaled on the transverse shaft 52, as shown in Fig. 4. The spur pinion 53 is connectible to the shaft 32 for rotation therewith by a multiple disc clutch 58, of a usual design, having improved operating means to be later described whereby the clutch may be controlled to effect drive of the spur pinion 53 by the shaft 32 at variable speeds. The worm wheels 5I, 51 are selectively connectible to the shaft 52 to effect drive of the latter at either a predetermined high speed or at any of a wide range of relatively low speeds, and the means for connecting these worm wheels to the shaft comprises for each worm wheel an interlocking clutch mechanism generally designated 59 and 69, respectively, and including, as shown in Fig. '7, interlocking clutch plungers 6| guided within radial bores 62 formed in the hub of the worm, wheel controlled thereby. These clutch plungers are normally held in their rearmost position by coiled springs 53, and when in their connected position are interlocked with longitudinal grooves 64 formed on the shaft 52. The mechanism for selectively operating the sets of clutch plungers for connecting either the worm wheel 5| or 51 to the shaft 52 comprises a shipper ring 65 surrounding the hubs of the worm wheels and movable axially along these hubs by means of a pivoted shipper yoke 66 having an operating shaft 61, and a suitable operating han.- dle 68, as shown in Fig. 7. The opposite sides of the shipper ring.65 are provided with internal cam surfaces S9, 'IB engageable with complementary siufaces on the clutch plungers so that when the shipper ring is moved into one position or the other, one set or the other of the clutch plungers is slid inwardly into interlocking relation with the grooves 64 on the shaft 52.

In this instance the feed operating and controlling members 9 and I0 are in the form of winding drums, and the feed operating and controlling elements I and I2 are in the form of cables or ropes wound upon the drums. These drums are. arranged in coaxial relation with the shaft 52 at the opposite sides of the machine frame, and are journaled upon the outwardly projecting ends of the shaft in the manner shown in Fig. 4. The drum IIJ, as shown in Fig. 4, is composed of three parts, including a central winding surface forming member II and end flanges 12 and 13, the parts being rigidly held in assembled relation by transverse bolts 14. The

hubs of the drum flange members are rotatably mounted on bearing sleeves |5, 'i5 surrounding and supported on the shaft 52. The drum I0 is connectible in driving relation with the shaft by means of clutch discs i6 securedto the drum and interleaved with clutch discs Vl secured to the shaft 52. The drum is held against axial displacement on the shaft by means of a split collar 'i8 and a .split washer 'i9 held in position by a sleeve 80. The co1lar18 and washer i9 are held in position between a shoulder 8| on the shaft and an outer flange 82 integral with the shaft. The drum 9 is similarly constructed` and is similarly journaled on the shaft'and is connectible to the shaft by a similar multiple disc clutch. The operating means for the disc clutches Within the drums 9 and I0v for selectively connecting the drums `to the shaft 52V herein comprises, for each clutch, pivoted lever elements 83 interposed between sets of the clutch discs and acting o-n a pressure plate 84 for each set, these `levers projecting inwardly through apertures 85 formed in the shaft in the manner shown in Fig. 4. Extending centrally through the shaft 52, which is herein hollow, is an operating'rod 86 having fixed thereto at its opposite ends at the opposite sides of the machine, operating'handles 8l and 88. The hubs 89 of these handles are slidably guided within the shaft bore and have clutch teeth 90 connectible to clutch teeth formed on a clutch applying element 9| threadedly engaged at 92 within the shaft bore, this applying element engaging the inner ends of the clutch operating levers 83. It will thus be seen that when the handle 81 is slid inwardly from the position shown `in Fig. 4, it is clutched to the operating element9l, and upon rotation of the handle the element 9| is rotated, and due to its threaded connection with the shaft, is moved axially inwardly, thereby swinging the levers 83 to effect spreading of the pressure plates 84, thereby to apply the clutch, and as a result, the drum lll is connected in driving relation with the .shaft 52. When the control rod 85 is slid outwardly '5. in the opposite direction, the handle 8T is disconnected from the operating element 9|, while the handle 80 is connected to its cooperating operating element, and upon rotation of the handle 88. the clutch within the drum 9 is applied,

1,; connecting the drum 9 in driving relation with the shaft. It is therefore evident that thedrurns 9 and l0 may be separately or simultaneously connected in driving relation with the shaft 52.

The improved operating mechanism for the friction clutch 58 for effecting drive of the spur as shown in Fig. 6.

pinion 53 at variable speeds from the shaft 32 comprises, as shown in Figs. 4 and 6. a sleevel 93 journaled on the shaft 52 and clutched at 94 to the hub of the worm wheel 5|. Formed on this sleeve 93 is a cam element 95 having a plurality, herein four, of cam projections 96, and co operating with the cam surfaces on this cam element is an operating lever 9i fulcrumed for plv'- otal movement at 98 on an operating rod 99, The rod 99 is externally threaded for engagement with an operating handle |90, this handle in turn having its hub por tion threadedly connected at i0! within the rear end wall of the feed frame. The lever 9'! is pivotally connected at |02 to an element |03, this element having threaded therein an operating rod |04. The threaded connection of the rod with the element |03 affords means for axially adjusting the rod, and the rod is held in its adjusted position by a lock nut |05. The rearward end of the rod |04 is provided with an enlargement |0B presenting a shoulder |01, and a spring |08 encircling the rod is co-mpressed between a collar |89 abutting an adjusting nut li threadedly connected to the rod and a collar slidably mounted on the rod and normally engaging the shoulder |97. The enlarged rearward end Illia` of the rod passes through a trunnion device ||2 supported by a shipper member ||3 in the form of a bell-crank mounted for pivotal movement at Htl, this shipper member carrying at its opposite side from yits pivot, clutch applying elements ||5 underlying and engaging a clutch applying member Iiii for the clutch 58, this clutch applying member assuming the form of a ball thrust bearing. The trunnion device H2 comprises elements Hl, il'i pivotally mounted at ||8 on the upper extremity of the shipper member I3 and having concave recesses l I9 engaging the cylindricalsides of the` enlarged portion |90 of the rod in the manner shown in Fig. 8, the elements il?, |i'| abutting the rear face of the collar as shown in Fig. 6. The rod 99 and the hub of the handle |00 are provided with right and left hand threads, respectively, and upon rotation of the handle |00, the rod 99 is moved axially to vary the position of the fulcrum of the lever 9i. It will thus be seen that when the parts are in the position shown in Fig. 6

and the cam element is rotating, the cam projections engaging the lower extremity of the lever 9'! eifect swinging of the lever, thereby moving the rod |04 axially, increasing the tension of the spring |08 and through the Spring, collar and trunnion device H2, effecting swinging of the shipper member to apply intermittently the friction clutch 58. By adjusting the handle |00, the position of the fulcrum of the lever 91 may be changed to vary the time interval of application of the friction clutch. By moving the lever fu1- crum into its extreme inner position, the lower end of the lever is at all times held against the surface of the cam element, thereby effecting constant application of the friction clutch, the spring |03 compressing as the cam projections 95 engage and swing the lever. By moving the lever fulcrum to its extreme opposite position, the cam element may rotate while the friction clutch is at all times released, the lever swinging back and forth as the cam projections engage the same without applying the clutch. It will thus bey seen that the low speed worm gearing 55. 5l may be driven through the friction clutch 58 at any desired low speed between zero and a predetermined maximum, the worm 'gearing being driven intermittently through wide `of speeds and continuously at a maximum low speed. It will also be evident that when the friction clutches within the dr ms are applied and the worm wheel 5| is connected to the shaft 52 by the interlocking clutch device 55, the drums may be rotated in winding direction at a relativen ly high machine moving or hauiage speed, while when the friction clutch 50 is applied, and the worm wheel 5'! is connected to the shaft 52 by the interlocking clutch mechanism 55, the ldrums may bedriven in winding direction at a re1atively low feeding speed, andby varying the applicad tion of the friction clutch 5B, the drums maybe driven at any desired feeding speed between zero and the maximum low feeding speed. The drums may be simultaneously connected to the shaft 52, or one or the other may be released therefrom, as desired, it also being possible to release both drums from the shaft. By moving the shiplll per ring in the intermediate position shown in Fig. 4, both of the interlocking clutch mechanisms 59, 60 may be released, thereby permitting the shaft 52 to remain stationary while the worm wheels 5|, 51 both rotate.

From the foregoing description, the mode of operation of the improved feeding mechanism will be clearly apparent, and as the use of room and pillar coal mining machines of the type disclosed is well understood by those skilled in the art, a detailed description of the mode of operation would be a needless repetition. The machine may be moved from place to place by connecting the high speed gearing by the interlocking clutch mechanism in driving relation with the drums. The machine may be fed at any desired speed from its maximum low speed down to zero, by proper adjustment of the fulcrum of the lever 91. The cutter bar may be sumped beneath the coal by the use of the feeding and controlling cables, and the machine fed along the coal face by the feed cable under the complete control of the operator through manipulation of the handle IUS and the friction clutch within the feed drum, the machine being guided during its transverse movement by means of the controlling cable under the control of the friction clutch within the controlling drum. Overloading will be prevented, in the illustrative embodiment shown in the drawings, by the presence of the spring 63 in the low speed drive mechanism. The feed drive may be disconnected merely by releasing the friction clutch within the feed drum or by releasing the variable speed friction 58.

As a result of this invention, it will be noted that an improved mining machine feeding mechanism is provided which is of a rugged and compact character and which is particularly adapted to use in coal mining machines of the room and pillar type wherein at times substantial variations in the feeding speed are of importance. It will further be noted that a continuous low feed and an intermittent low feed are both available by the same mechanism, permitting in a single` machine either type of feed if there is any choice, under peculiar circumstances. Further advantages Will be apparent to those skilled in the art.

While there is in this invention specically described one form which the invention may assume in practice, it Will be understood that this form of the saine is shown for purposes of illustration and that the invention may be modied and embodied in various other forms Without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Pat-ent is:

1. In a mining machine, kerf cutting mechanism including a kerf cutter actuating element, a motor for rotating said element, and machine feeding means driven by said element including a flexible feed member engaging feeding member and high and low speed driving mechanism for said feeding member, said low speed mechanism including a clutch coaxial with said element and through which said feeding member is driven at a low speed, and means driven by an element of said high speed mechanism for automatically intermittently applying and releasing said clutch.

2. In a mining machine transmission mechan nism, a driven member, and motor operated high and low speed driving means for said driven member, said low speed driving means including a friction clutch through which said driven member is driven at a low speed, said clutch including relatively rotatable alined clutch elements and a coaxial reciprocable clutch operating member operative when loaded to connect said alined elements together for equiangular rotation, and said high speed driving means having a high speed terminal driving element and said low speed driving means having a low speed terminal driving element, and means driven at a high speed, greater than the speed of said low speed terminal driving element, by said terminal driving element of said high speed driving means for automatically shifting said clutch operating member for intermittently applying and releasing said friction clutch at timed intervals.

3. In a mining machine transmission mechanism, a driven member, and motor operated high and low speed driving means for said driven member, said low speed driving means including a friction clutch through which said driven member is driven at a low speed, said clutch including relatively rotatable alined clutch elements and a coaxial reciprocable clutch operating member operative when loaded to connect said elements together for equiangular rotation, and said high speed driving means having a high speed terminal driving element and said low speed driving means having a low speed terminal driving element, a cam rotatable at a high speed, greater than the speed of said lovf speed terminal driving element, with Said terminal driving element of said high speed driving means, and operating means actuated by said cam for automatically shifting said clutch operating member for intermittently' applying and releasing said low speed clutch at timed intervals.

4. In a mining machine transmission mechanism, a motor driven shaft disposed on a vertical axis, a high speed gear train including a gear coaxial with and driven by said shaft, a low speed gear `train including a different gear coaxial with said shaft, a clutch for connecting said latter gear to said shaft for driving thereby, means driven by said high speed gear through said high speed gear train independently of said low speed gear train for automatically intermittently applying and releasing said clutch, a driven member, and means for selectively connecting said driven member to either of said gear trains for driving thereby.

5. In a mining machine transmission mecha.- nism, a motor driven shaft disposed on a vertical axis, a high speed gear train including a gear fixed to said shaft for driving thereby and a gear meshing therewith, a low speed gear train including a gear coaxial with said shaft, a clutch for connecting said latter gear to said shaft for driving thereby, and a gear driven by said latter gear and arranged coaxially with said second gear, means actuated by said second gear for intermittently applying and releasing said clutch, a driven member, and means for selectively connecting said second and fourth gears alternatively in driving relation with said driven member.

6. In a mining machine transmission mechanism, a motor driven shaft disposed on a vertical axis, a parallel shaft, a high speed gear fixed to said first shaft and a gear meshing therewith, a low speed gear coaxial with said first shaft, a clutch for connecting said latter gear to said first shaft for driving thereby, a gear meshing with said latter gear and fixed to said parallel shaft, a gear driven by said parallel shaft and arranged coaxially with said second gear, means actuated by said second gear for intermittently applying and releasing said clutch, a driven mem- "ber, and means for selectivelyconnecting said secondand fifth mentioned gears alternatively in driving relation with said driven member.

7. In a mining machine ytransmission mechanism, a driven member, a drive shaft therefor, a high speed driving element fixed to said shaft, a high speed member driven by said high speed driving element and arranged on an axis at right angles to the axis of rotation of said high speed driving element, a low speed driving element coaxial with said shaft, a clutch coaxial with said shaft for connecting said low speed driving element to said'shaft for driving thereby, and means driven by said member driven by said high speed driving element independently of said low speed driving element for automatically intermittently applying and releasing said clutch at timed intervals.

8. In a mining machine, kerf cutting mechanism including a kerf cutter driving element, a drive shaft driven thereby, a high speed driving element fixed to said shaft, a low speed driving element coaxial with said shaft, a clutch coaxial with said shaft for connecting said low speed driving element to said shaft, means driven by said high speed driving element for intermittently applying and releasing said clutch, a `driven member, and means for selectively connecting said high and low speed driving elements alternatively in driving relation with said driven member. i

9. In a mining machine transmission mechanism, a final driving member for delivering at a point beyond said transmission mechanism the power put into the latter, and driving means for said final driving member including angularly related shafts, means for effecting driving of one of said shafts by the other and driving of Said final driving member by the first shaft including a driving element coaxial With one of said shafts, means operative when driven by said driving element to transmit rotation to said other shaft, a friction clutch for connecting said driving element to said shaft With Which it is coaxial for driving by the latter, said clutchincluding alined, relatively rotatable friction clutch elements coaxial with said last mentioned shaft and an applying element movable axially relative to said last mentioned shaft for frictionally connecting said clutch elements for equiangular rotation, and means coaxial with said other shaft for automatically shifting said clutch app-lying element for effecting intermittent application of said friction clutch at timed intervals to cause said driving element to effect drive of said other shaft.

10. In a mining machine transmission mechanism, a vertical shaft, a horizontal shaft to be driven thereby, driving connections between said shafts including a driving element coaxial with said vertical shaft, means operative when driven by said driving element to transmit rotation to said vhorizontal shaft, a friction clutch coaxial with said vertical shaft for connecting said driving element thereto for driving thereby, said clutch including alined relatively rotatable friction clutch elements and an applying element movable axially relative to said coaxial shaft for frictionally connecting said clutch elements together for equiangular rotation, and means having a driving element coaxial with said horizontal shaft for automatically shifting said clutch applying element for effecting intermittent application of said friction clutch at timed intervals to cause drive of said horizontal shaft through said friction clutch.

11. In a mining machine transmission mechanism, a driven member, and motor operated driving means therefor including a clutch through which said driven member is driven, a rotatable cam disposed with its axis arranged at right angles to a line parallel With the clutch axis, a pivoted lever engaging said cam for swinging thereby, yielding clutch operating means actuated by said lever for intermittently applying said clutch, and adjustable means for changing the position of the lever fulcrum.

12. In a mining machine transmission mechanism, a driven member, and motor operated driving means for said member including a clutch disposed with its axis vertical, a rotatable cam member disposed with its axis horizontal, a lever engaging said cam for swinging thereby, Vyieldable clutch operating means actuated by said lever for intermittently applying said clutch, and adjustable means for changing the position 'of the lever fulcrum.

13. In a mining machine transmission mechanism, a drive control clutch, and mechanism for automatically effecting` intermittent application and release of said clutch at timed intervals including a cam havin-g a cam surface, a lever swingable in planes at right angles to the cam axis and engaged and actuated by said cam, and a reciprocable clutch operating element actuated by said lever and having its axis of reciprocation at right'angles tothe axis of cam rotation.

14. In a mining machine transmission mechanism, a transmission shaft extending longitudinally of the machine, parallel vertical shafts, means driven by said longitudinal shaft for driving said parallel vertical shafts, and high and low speed gearings driven by said parallel shafts, respectively, the drive for said low speed gearing including a drive control clutch coaxial with the vertical high speed gearing drive shaft, said clutch including alined relatively rotatable clutch elements and a coaxial reciprocable clutch loading member for connecting said clutch elements for equiangular rotation, and means actuated by an element of the high speed driving gearing for automatically shifting said clutch loading member for intermittently applying and releasing said low speed clutch at timed intervals.

15. In a mining machine transmission mechanism, a transmission shaft extending longitudinally of the machine, parallel vertical shafts driven by said longitudinal shaft, and high and low speed gearings driven by said parallel shafts, respectively, the drive for said lovv speed gearing including a drive control clutch coaxial with the vertical high speed gearing; drive shaft, said clutch including alined relatively rotatable clutch elements and a coaxial reciprocable clutch loading member for connecting said clutch elements for equiangular rotation, and means actuated by an element of the high speed driving gearing for automatically shifting said clutch loading member for intermittently applying and releasing said low speed clutch at timed intervals, said automatic clutch applying and releasing means including a cam driven by said vertical high speed gearing drive shaft and clutch operating connections actuated by said cam.

16. In a mining machine transmission mechanism, a driven member disposed on a horizontal axis extending transversely of the machine, and motor operated driving mechanism for said member for rotating the latter at a number of relatively diferent low feeding speeds including a driving member disposed on a vertical axis, a

friction clutch coaxial with said driving member for connecting the latter in driving relation with said driven member, and motor operated means for automatically intermittently applying and releasing said clutch including an eccentric member rotatable about an axis alined with the axis of said driven member.

17. In a mining machine transmission mechanism, a driven member disposed on a horizontal axis extending transversely of the machine, and motor operated driving mechanism for said member for rotating the latter at a number of relatively diiferent low feeding Speeds including a driving member disposed on a vertical axis, a friction clutch coaxial with said driving member for connecting the latter in driving relation with said driven member, and motor operated means for automatically intermittently applying and releasing said clutch and driven by an element driven by said driving member, said element rotatable about an axis coincident with the axis of said driven member.

18. In a mining machine transmission mechanism, a driving member disposed on a vertical axis, a driven member disposed on a horizontal axis, means driven by said driving member for driving said driven member, a second driven member coaxial with said first driven member, means including a clutch coaxial with said driving member for connecting the second driven member in driven relation with said driving member, and means actuated by said rst driven member for automatically intermittently applying and releasing said clutch.

19. In a mining machine transmission mechanism, a driving member disposed on a vertical axis, a driven member disposed on a horizontal axis, means driven by said driving member for driving said driven member, a second driven member coaxial with said first driven member, means including a clutch coaxial with said driving member for connecting the second driven member in driven relation with said driving member, and means actuated by said rst driven member for automatically intermittently applying and releasing said clutch including a cam rotatable with said first driven member.

20. In a mining machine transmission mechanism, a friction clutch disposed with its axis vertical, said clutch including alined relatively rotatable friction clutch elements and a reciprocable clutch loading member coaxial with said clutch elements for frictionally connecting the latter for equiangular rotation, means for automatical- 5 ly shifting said clutch loading member for interactuated by said cam, and a member driven through said clutch and journaled coaxially with said cam.

21. In a mining machine transmission mechanism, parallel vertical shafts, fast and slow speed worms secured to said shafts respectively, a horizontal shaft, relatively rotatable fast and slow speed worm wheels coaxial with said horizontal shaft and meshing with said worms respectively, means for selectively connecting said worm wheels in driving relation with said horizontal shaft, means for driving said vertical shaft to which said fast speed Worm is secured, means including a clutch for connecting said other vertical shaft in driven relation with said vertical fast speed worm shaft, a cam rotatable with said fast speed worm wheel, and means actuated by said cam for automatically intermittently applying and releasing said clutch at timed intervals.

22. In a mining machine transmission mechanism, a vertical driving shaft, a shaft parallel with said vertical driving shaft, means including a clutch coaxial with one of said shafts for connecting said second mentioned shaft in driven relation with said vertical driving shaft, a fast speed worm driven by said vertical driving shaft, a slow speed worm driven by said parallel vertical driven shaft, fast and slow speed worm wheels meshing with said worms respectively, a cam rotatable with said fast speed worm wheel, and clutch operating means actuated by said cam for automatically intermittently applying and releasing said clutch.

23. In a mining machine, kerf cutting mechanism including a kerf cutter driving element, and

feeding mechanisms driven by said kerf cutter driving element including a shaft coaxial with and driven by said kerf cutter driving element, a feeding member, a friction clutch coaxial with said shaft for connecting said feeding member in driven relation with said shaft, and means driven by said shaft for automatically intermittently applying and releasing said clutch at timed intervals.

24. In a mining machine, kerf cutting mechanism including a kerf cutter driving element disposed on a vertical axis, a motor driven shaft for driving said cutter driving element, and feeding means for the machine including a low speed gear train driven by said motor driven shaft and including a driving element coaxial with said cutter driving element, said low speed gear train also including a friction clutch, and means driven by said motor driven shaft for intei-mittently applying and releasing said clutch at timed intervals.

MORRIS P. HOLMES. 

